The present invention relates to adjusting a display on a monitor. More particularly, the present invention relates to automatically adjusting size, center, and geometrical distortions on a monitor.
Monitors are an important element in computer systems. Typically, monitors are coupled to a personal computer and provide the user with a visual interface of the personal computer""s data contents. Although, current monitors offer unique packaging and different display qualities, the cathode ray tube (xe2x80x9cCRTxe2x80x9d) remains an integral element in the design of most monitors. The CRT converts an electrical signal into visual information using an electron beam that is modulated and deflected onto a cathodoluminescent screen surface.
Improvements in monitor designs has led to computer systems that provide the user with compact and sharp displays. The design improvements, however, have not led to improvements in the display orientation of the monitors. Conventional monitors typically have built in controls to adjust the positioning and sizing of images. The controls allow the user to alter the deflection angle of the electron beam by increasing/decreasing the magnetic flux created by the deflection coils in a CRT device.
FIG. 1 illustrates one embodiment of a prior art CRT. CRT 100 includes a vacuum tube 106 coupled to screen 110. Deflection coil 105 is used to position magnetic flux 115 around electron beam 120. A control signal (not shown) allows a user to adjust the magnitude of the electric signals on deflection coil 105, thus adjusting the magnitude of magnetic flux 115. The change in magnetic flux 115 increases/decreases deflection angle 130 form the Z-axis, thus varying the position of electron beam 120 on screen 110. Varying the position of beam 120 allows the user to vary the position and orientation of an image displayed on screen 110. Although using control inputs to adjust images on screen 110 creates provides the user with greater flexibility, manual control inputs create a number of disadvantages.
One disadvantage of the conventional control inputs is that the CRT requires multiple adjustments. Typically, CRT""s require adjustments because magnetic flux 115""s alignment is easily skewed by extraneous magnetic fields. For example, the earth""s magnetic field causes distortion in a monitor display. Similarly, an extraneous electrical device can cause a magnetic field that causes distortion in a monitor display. Accordingly, in conventional monitors, the user is required to locate different control inputs on the monitor and manually adjust the distorted image.
FIG. 2 illustrates typical distortions in a conventional monitor display. Image 210 shows an image that is shifted upwards and increase in width as electron beam 120 scans up the vertical axis of screen 110. Conversely image 230 show an image that is shifted downwards and increase in width as electron beam 120 scans down the vertical axis of screen 110. Additionally, images 220 and 240 illustrate image distortion caused by a negative degree rotation and a positive degree rotation, respectively. Accordingly, in the prior art the user is required to adjust the distortions illustrated in FIG. 2 via manual controls.
Another disadvantage of manual control inputs occurs during the manufacturing of computer systems. In particular, during the manufacturing process of computer systems installation of a new monitor requires adjustment of the monitor display to align an image or remove image distortions. The adjustment is necessary because the manufacture is unable to anticipate the different magnetic variance that affect each computer system. Manual adjustment of monitors during the manufacturing process, however, is costly and tedious.
To automate image alignment and distortion correction of newly manufactured monitors, some manufactures introduce a camera and a microprocessor to the manufacturing process. The camera records an image displayed on the monitor and the processor adjusts the displayed image on each monitor. Although the camera and microprocessor automate monitor adjustment, the camera and microprocessor are not available to users outside the manufacturing process. Thus, in non-manufacturing environments the user adjusts distortions via manual controls. Additionally, the camera and microprocessor reduce efficiency in the manufacturing process because the camera and microprocessor introduces extraneous steps to the manufacturing process.
An apparatus to automatically adjust image distortions is disclosed. The apparatus comprises a driver operable to generate images on a screen. The apparatus further comprises a plurality of sensors coupled to the screen. Each sensor detects whether the area under the sensor is illuminated. The apparatus further comprises a circuit coupled to the plurality of sensors and the driver. The circuit is configured to adjust the driver based on illumination of a sub-set of the plurality of sensors. A method for automatically adjusting image distortions of a video monitor is also disclosed.
Other features and advantages of the present invention will be apparent from the accompanying drawings and from the detailed description that follows.